We have read with great interest the article by Reyes et al.,1 which lays out a prospective work done in an A&E department applying a rapid HIV diagnosis test with a voluntary exclusion (opt-out) strategy. In this work, a low prevalence of new HIV diagnoses among the participants was found.
We agree with the authors that performing universal opt-out screenings in an A&E department corresponding to a population of low prevalence would have little impact in terms of public health. In a meta-analysis2 that included 28 screening studies (with voluntary inclusion and exclusion) performed in A&E departments, we found that the prevalence detected by an opt-out strategy was 0.40% (373 cases), compared with the voluntary inclusion (opt-in) strategy, which was 0.52% (419 cases).
We agree with the authors with regard to the promotion of voluntary screening, especially in populations with greater risk (targeted voluntary inclusion) and not to perform universal opt-out screening due to the greater occurrence of false positives. Although some recommendations emphasise the opt-out strategy when the prevalence of HIV infection is >0.1%3,4; it has been seen that in our environment, in primary care, there are studies that report prevalence of 0.35%.5
On the other hand, the cost to the national health system of an undiagnosed HIV-infected patient is very high, not only because of the delay in diagnosis and its consequences for the patient's health, but also because it remains a source of infection for others.
Finally, we believe that in the specific case of A&E departments, the strategy that is likely to be most efficient is the targeted opt-in strategy.
Please cite this article as: Henriquez Camacho C, Losa JE, Pérez Molina J, Villafuerte P. Cribado de virus de inmunodeficiencia humana. Enferm Infecc Microbiol Clin. 2018;36:256.